The Houston Zoo's baby giraffe has proven to be a formidable fighter against a life-threatening bone infection.

The Masai calf named Yao Ming, who was born Feb. 25, continues to make progress after undergoing surgery last month to remove infected bone from his right front shoulder. Veterinarians also found an infection in Yao's left rear leg, which has healed quicker because it did not affect the bone, officials said.

"We're happy with his progress. It seems like he's headed in the right direction," said John Register, a supervisor at the zoo. "Obviously we're taking it day-by-day for him. He is progressing and getting better every day, so we're very hopeful."

Zoo personnel are monitoring the baby giraffe around the clock as he sticks close to his attentive mom, Neema, Register said.

A week after Yao's birth, keepers noticed that he was favoring his rear left leg. When the limp gradually became worse, zoo veterinarians X-rayed the leg and found no evidence of bone damage. They put the calf on antibiotics and other medication, including anti-inflammatory analgesics.

When the situation didn't improve, zoo officials called Dr. Wyatt Winchell of Brazos Valley Equine Hospital in Navasota. He determined that Yao had developed a bone infection in his right shoulder, and began an aggressive treatment regimen that included flushing the joint, removing the damaged tissue and infected bone, and administering stronger antibiotics.

After the operation, Yao was putting weight on his legs, although not as much on the two injured ones. Now, he's moving better every day, Register said.

"Each morning he gets some oral meds, including antibiotics and pain medication," Register said. "Then we'll walk him around. We want to make sure he gets physical exercise and physical therapy."

Much of the time, Yao, named after the former Houston Rockets star player, does what baby giraffes do - explores his habitat and spends time with mom, Register said.

"She's a terrific mom and very attentive to her baby," he said. "She cleans him up all the time and lets him nurse."

She even stays nearby when zoo veterinarians move Neema to a separate enclosure in order to inspect Yao.

"There have been times where we've been working on her son, and she's close enough so she can actually reach down with her head and lick her son's face, and make sure everything's OK," Register said. "She sees everything."